/**
 * Copyright 2019 Anthony Trinh
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package ch.qos.logback.core.util;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * @author Ceki G&uuml;c&uuml;
 */
public class EnvUtil {

  private static final Pattern versionPattern = Pattern.compile("^(1\\.)?([0-9]+)");

  private EnvUtil() {}

  static private boolean isJDK_N_OrHigher(int n) {
    Matcher matcher = versionPattern.matcher(System.getProperty("java.version", ""));
    if (matcher.find()) {
      return n <= Integer.parseInt(matcher.group(2));
    }
    return false;
  }

  static public boolean isJDK5() {
    return isJDK_N_OrHigher(5);
  }

  static public boolean isJDK7OrHigher() {
    return isJDK_N_OrHigher(7);
  }
}
